Collision Detection and Coordinated Compliance Control for a Dual-Arm Robot Without Force/Torque Sensing Based on Momentum Observer

Dual-arm robots have widely used for fine manipulation, such as assembly, maintenance, and payload carrying and handling. In order to ensure the safety during human–robot interaction, it is necessary for a robot to detect unexpected collisions in real time and make fast and accurate responses. In this paper, we propose a practical collision detection and a coordinated compliance control method based on the momentum observer for a dual-arm robot without any force/torque sensors. The interactions among the dual-arm robot, human, environment, and object to be manipulated are fully considered. The momentum observer is designed by combining the dynamics of the dual-arm robot. It is used to detect the collision and identify the mass of the object to be manipulated. The coordinated compliance control of the dual-arm robot is then realized by the impedance control of each arm and object, under the coordinated behavior during performing common task and manipulating common objects. The desired force and the trajectory of each arm's end-effector are optimized based on the minimum energy criterion. The simulation and experimental results of typical tasks verify the proposed method.